Many portable computer devices such as laptop computers, personal digital assistants (PDAs) and portable video game consoles use liquid crystal displays (LCDs) as an output display device. A problem that such devices contend with is battery life. Battery life in portable electronic equipment that use a liquid crystal display is adversely affected when a color-capable liquid crystal display is operated in a so-called true-color simulation mode.
True-color simulation on a color LCD attempts to improve color quality by a technique known as dithering. Dithering is a process by which true color can be simulated or approximated on an LCD by having successive frames of an image displayed with different colors in each successive frame so as to blend or merge the color displayed in one frame, with the color displayed in a subsequent frame thereby giving an observer the impression that the displayed color is a mix or dither of the different colored pixels in each frame.
A problem with true color simulation on a LCD is the amount of electric power that true color simulation requires. Because a liquid crystal display is a capacitive device, each pixel color change from one frame to the next requires charging and discharging a capacitor. Charging and discharging a capacitor in order to provide dithering, consumes more power than a non-dithered display. Although dithering can provide better picture quality, dithering consumes more power than a non-dithered display. In portable computer devices that use LCDs, a method and apparatus by which a portable computer device user can select either a reduced-power consumption mode or a higher-picture quality dithering mode would be an improvement over the prior art.